SHALLOW-WATER STARFISHES 173 



dian Geological Survey) ; off Victoria, British Columbia, in 25 fath- 

 oms (C. F. Newcombe, Prov. Mus. B. C), very large. 



ORTHASTERIAS BIORDINATA Verrill, sp. nov. 



Plate Lxiii, figures I, 2 (general of type) ; plate lxxxii, figures 2-2b (spines 



and pedicellariae). 



The two type-specimens are very much alike and nearly of the 

 same size. Radii of the one figured, 8 mm. and 88 mm. ; ratio, 

 1 : 1 1 ; radii of the other, 9 mm. and 85 mm. ; ratio, 1:9:5. 



Rays five, long, slender, very gradually tapered, rather acute, well 

 rounded above, and furnished with three regular rows of well 

 spaced, elongated spines, one to a plate, except near the ends of the 

 rays, where there are five rows, and the spines are closer together. 

 Isolated spines also stand on the transverse ossicles, here and there. 

 The dorsal spines are regularly clavate, evenly fluted distally, with 

 the tips obtusely rounded. 



They stand on elevations of stout, lobed plates. The median 

 row is distinct, because the spines are about twice as many, though 

 of about the same size and length. The center of the disk is occu- 

 pied by a prominent five-lobed plate, bearing a spine, and with five 

 stout ossicles radiating out from its lobes, in line with the median 

 rows of the rays, but connecting with five radial spine-bearing 

 plates of the disk, which form a pentagon. 



Alternating with these, and a little farther away, are five larger 

 interradial plates, each bearing a spine of larger size. 



The dorsal pore is small and surrounded by minute papills. It lies 

 between t^o lobes of the central plate and in an interradius next to 

 that occupied by the madreporite, which is large, very round, and 

 with fine gyri. 



The spines are surrounded by close wreaths of very small minor 

 pedicellariae which are often subbasal, but frequently at mid-height, 

 or distal, and then are attached to the edges of a sheath. 



The superomarginals fomi a very regular row, one to a plate, of 

 rather longer and more slender fluted spines. The inferomarginal 

 row is double, with two spines to a plate ; these spines are dis- 

 tinctly longer, more slender, and less clavate than the dorsals, but 

 fluted in the same way. Alternate superomarginals are spineless. 



The peractinals are smaller; on several rays they extend only on 

 the proximal third of the ray ; on others to the distal fourth. 



The adambulacral spines are slender, regularly diplacanthid, 

 widely divergent, forming two remarkably regular pectinate rows, 



